Company's top brass has also taken hits for not publicly engaging on their site

It's been sort of a rough week for Google+.

Fresh on the heels of reports that activity on Google's social network -- the tech giant's effort to cut into Facebook's empire -- has dropped sharply since its public rollout, a Google engineer accidentally shared a memo calling the site "a knee-jerk reaction" and a "study in short-term thinking."

Google+, which launched by invitation only in June, has been a hit among so-called "tech elite" journalists, bloggers and others heavily immersed in the technology and social-networking world. But adoption by the general public, namely the people behind Facebook's roughly 800 million accounts, has been slower.

Engineer Steve Yegge blames, in part, blames Google's failure to share the site's programming platform with developers who could have built games and other apps to make it a more robust online hangout.

How do we know? He accidentally shared what was supposed to be an internal memo with the world.

On Google+.

"Google+ is a knee-jerk reaction, a study in short-term thinking, predicated on the incorrect notion that Facebook is successful because they built a great product," Yegge wrote in what was supposed to be an internal memo. "But that's not why they are successful. Facebook is successful because they built an entire constellation of products by allowing other people to do the work. So Facebook is different for everyone."

"Some people spend all their time on Mafia Wars," he wrote. "Some spend all their time on Farmville. There are hundreds or maybe thousands of different high-quality time sinks available, so there's something there for everyone."

What's worse is that, in a follow-up post, he mistakenly made the memo public because he's "not what you might call an experienced Google+ user." The post said he'd talked to Google's public-relations department and it was understanding about his mistake.

"(T)hey went out of their way to help me understand that we're an opinionated company, and not one of the kinds of companies that censors their employees," he wrote.

The memo comes on the heels of a report from Chitika Insights, a Web analytics firm, saying traffic on Google+ has plummeted 60% since it opened to the public on September 20.

On that day, Chitika reported, traffic spiked 1,200% from before, when an invitation was required to join the network. But, just a week later, it had fallen back to roughly the same level it was before the public rollout.

"It would appear that although high levels of publicity were able to draw new traffic to Google+, few of them saw reason to stay," Chitika said in its report, released Friday.

The firm puts forward two theories: 1) that the supply of social-media users is limited (and, presumably, mostly already on Facebook) and 2) that while it has a "striking new interface, rapid release of new features, and focus on user interaction," Google+ doesn't offer much that's truly unique.

While Web analytics can be an imprecise science (companies use different programs and, as such, often end up with different figures), the report spoke to the general perception of how the network has fared.

Mashable's Ben Parr noted in an October 4 post that the low level of public usage by Google's top brass (he counted a total of 22 posts from co-founders Larry Page and Sergey Brin) sends the wrong message.

"It doesn't matter how you slice it," he wrote. "If Google's management truly believed in Google+ as the future of the company, they would be more engaged."